Working with Panasonic, Toyota gains expertise in lithium-ion battery technology

The ability to monitor the individual battery cell conditions is fast becoming a key metric, as a closely-held trade secret, which can provide strategic depth and a competitive advantage to companies in the looming transportation sector which is set to radically change itself by the end of this decade.

Toyota Motor Corp is all set to storm into the all-electric car market after it gained sufficient expertise in combating and taming the volatile lithium-ion battery technology. It has stated that it can now provide increased power to its vehicles at no significant extra cost.

While its rivals, including Nissan Motor Co and Tesla Motors had begun adopting lithium-ion battery technology almost a decade ago, Toyota’s engineering efforts were held due to costs, size and safety concerns.

The recent Galaxy Note 7’s smoking fiasco faced by Samsung has been attributed to its unstable Lithium-ion battery technology.

Toyota has disclosed that its soon to be launched Prius Prime will use lithium-ion batteries and will have enough power to throttle the car at 37.3 miles (60 kms) when it is fully charged and before the gasoline engine kicks in.

Due to varying methodologies in how an electric car’s range is tested, the Prime’s 37.3 miles range will be listed in the United States as around 25 miles 40.2 kms).

With safety concerns becoming increasingly more prominent around lithium-ion batteries, Toyota disclosed that the safety aspect is being given increased scrutiny. Lithium-ion batteries can catch fire if they aren’t properly designed, tested and manufactured. Increased quality assurance throughout the manufacturing process will be vital.

“It’s a tall order to develop a lithium-ion car battery which can perform reliably and safely for 10 years, or over hundreds of thousands of kilometers,” said Koji Toyoshima, the chief engineer for the Prius.

Toyota’s confidence in its battery’s technology comes from its improved safety and stability control technologies that monitors the temperature and condition of each of the 95 cells in its new battery pack precisely.

“Our control system can identify even slight signs of a potential short-circuit in individual cells, and will either prevent it from spreading or shut down the entire battery,” said Hiroaki Takeuchi, a senior Toyota engineer involved in the development.

Toyota has been working with Panasonic Corp, which produces Li-ion batteries for Tesla and in the process it has improved its precision in battery cell assembly thus ensuring that the chemistry in its batteries are free of impurities.

Even a microscopic introduction of impurities, including metal particles, can lead to overheating problems, trigger short-circuits and can cause a potential explosion.

“The environment where our lithium-ion batteries are produced is not quite like the clean rooms where semiconductors are made, but very close,” said Takeuchi.

“State of charge management, safety management and algorithm development is becoming one of the higher tiers of proprietary internal development,” said Eric Rask, principal research engineer at Argonne National Laboratory, a U.S. Department of Energy facility outside Chicago.

“It’s very internal, very strategic, and companies are seeing management algorithms as a competitive advantage.”